PMOS redefines PCOS: recognising hormones, insulin and metabolism

Polycystic ovary syndrome (PCOS) is now polyendocrine metabolic ovarian syndrome (PMOS). Here's why this matters more than a name change.

A landmark paper published in The Lancet and presented at the European Congress of Endocrinology in Prague officially renamed polycystic ovary syndrome to polyendocrine metabolic ovarian syndrome, or PMOS.

The consensus involved more than 50 patient and professional organisations and reflects a growing global recognition that accurately naming a condition is foundational to understanding it and to delivering the care patients deserve.

It is a significant moment. And for those of us working in functional health and functional medicine, it is one we have been waiting a long time for.

The name was always the problem

PCOS. Polycystic ovary syndrome. Even the name told the wrong story.

For decades, women were told they had cysts on their ovaries. Sent for ultrasounds. Told there were cysts present, or told there weren't, and therefore maybe they didn't have the condition after all.

Here is the thing: the structures seen on ultrasound are not pathological cysts at all. They are arrested follicles, follicles that haven't matured properly and released an egg.

And why haven't they matured? Because of the hormonal environment surrounding them. Elevated insulin levels and elevated androgens directly disrupt the follicle maturation process. The follicles stall. They accumulate. They show up on a scan and get called cysts, and that single word has shaped how this condition has been understood, communicated, and treated for over half a century.

The result? The research has shown that this terminology led to significant diagnostic delays affecting up to 70% of those with the condition, and fragmented care. Seventy per cent. That means the majority of women living with this condition spent years, sometimes decades, without a clear diagnosis or an adequate treatment plan. Not because the condition was rare or difficult to identify. But because the name pointed in the wrong direction.

What PMOS actually is, and always has been

In the functional health world, we have long understood PMOS not as a reproductive condition but as a systemic metabolic one.

It is, at its core, a condition that affects how the body processes and uses energy. How it converts nutrients into fuel. How it responds to insulin. How it manages androgens. How it regulates inflammation. The ovaries are involved, but they are not the origin of the problem. They are where the consequences show up.

PMOS involves interacting disturbances in insulin signalling, androgen production, neuroendocrine pathways, and ovarian function, contributing not only to menstrual dysfunction and fertility challenges, but also to metabolic conditions including insulin resistance, increased cardiovascular disease risk, type 2 diabetes, and mental health conditions.

This is not a condition that belongs in the gynaecology department alone. It lives across endocrinology, metabolism, gut health, mental health, skin health, and cardiovascular health. It affects the whole woman. And it always has.

Why the new name gets it right

Let's break down what PMOS actually means, because every word in this name was chosen deliberately.

Polyendocrine because this is a condition driven by multiple interacting hormonal disturbances. Not one hormone. Not just the ovaries. Insulin, androgens, and neuroendocrine pathways are all involved. The endocrine system, the body's hormonal communication network, is dysregulated at multiple levels simultaneously.

Metabolic because this condition fundamentally affects metabolism. How the body uses energy. How it converts nutrients into fuel. How it manages insulin. How it clears waste and toxins. The metabolic dimension of this condition has been under-prioritised for too long, and naming it here changes what clinicians and researchers are required to address.

Ovarian because the ovaries are involved. The arrested follicles, the disrupted ovulation, the hormonal feedback loop that runs through ovarian function, all of this is real and relevant. The ovaries are part of the picture. They are just not the whole picture.

Syndrome, because this is a collection of symptoms. And this is perhaps the most important word of all.

The phenotypes and subtypes

No two women with PMOS look the same, and this is the part that doesn't get talked about enough.

PMOS is diagnosed when two of three criteria are met: ovulatory dysfunction, elevated androgens, and polycystic ovarian morphology on ultrasound. This produces four distinct phenotypes, each with a different metabolic and hormonal profile.

Phenotype A is the full classic presentation. All three criteria are present, with the most significant insulin resistance and metabolic disruption. This is the most commonly recognised picture.

Phenotype B has irregular cycles and elevated androgens but no polycystic morphology on scan. Metabolically, it closely mirrors Phenotype A, but because the ultrasound looks clear, this woman might frequently be told she doesn't have it.

Phenotype C has elevated androgens and the follicle pattern on scan, but her cycles are regular. She may be ovulating. Because her periods arrive consistently, she often doesn't get investigated at all, despite experiencing real androgen-driven symptoms like acne, hair loss, and excess hair growth.

Phenotype D is the normoandrogenic presentation. Irregular cycles and polycystic morphology, but androgens appear normal on standard bloodwork. She tends to present more mildly but still experiences significant cycle disruption, fatigue, and mood changes, and is often dismissed because she doesn't fit the typical image.

Sitting underneath the phenotypes are four functional subtypes that explain the root driver, and this is where the functional health world has always worked.

Insulin-resistant PMOS is the most common, affecting around 70% of cases. Elevated insulin drives the ovaries to produce excess androgens. Blood sugar dysregulation is at the centre of everything.

Inflammatory PMOS is driven by chronic low-grade inflammation that disrupts ovarian function and hormone signalling. Signs include headaches, joint pain, unexplained fatigue, skin issues like eczema, and bowel problems alongside the hormonal picture.

Adrenal PMOS involves the stress hormone pathway producing excess DHEA-S from the adrenal glands rather than the ovaries. This woman's symptoms might flare during high-stress periods, burnout, or major life changes. Standard androgen panels can miss this entirely if DHEA-S isn't tested.

Post-pill PMOS is a temporary hormonal disruption that can occur after stopping hormonal contraception. It can look identical to other presentations, but often resolves with the right nutritional support as the body recalibrates.

Most women have a blend of more than one subtype, but identifying the dominant driver is what changes the approach entirely. This is why one woman can follow a PMOS protocol and see dramatic shifts while another on the exact same plan sees nothing. It is not a failure of effort. It is a mismatch of approach.

What this means for the women living with it

For the women I work with as a hormone and metabolic health nutritional therapist, who have been managing this quietly for years, this name change matters in a way that goes beyond semantics.

It matters because the old name minimised what they were dealing with. It reduced a complex, systemic, lifelong condition to a question of whether there were cysts on their ovaries. It kept the conversation in the gynaecology room when it needed to be in the metabolic health room, the endocrinology room, and the nutrition room.

As one patient advocate who played a key role in the renaming process put it:

That clarity starts with a name that tells the truth.

Those of us in the functional health space didn't need a name change to understand that PMOS was a metabolic condition. We have been working with it that way for years, addressing insulin, inflammation, gut health, androgen excess, and nutrient deficiency as the root drivers, not just managing symptoms at the surface.

But language shapes everything. It shapes how conditions are researched. How they are taught in medical schools. How they are communicated to patients. How seriously they are taken.

PMOS is a truer name, and it is long, long overdue.

If you have been diagnosed with or suspect you might have what we now know as PMOS, and you want to understand what is actually driving your symptoms and what can be done about it, reach out for support.

References

Source: The Lancet, May 2026. Teede HJ et al. Polyendocrine metabolic ovarian syndrome, the new name for polycystic ovary syndrome: a multistep global consensus process. doi.org/10.1016/S0140-6736(26)00717-8